1. Field of the Invention
The present invention relates to a game apparatus and a storage medium storing a game program. The present invention particularly relates to a game apparatus and a storage medium storing a game program, which perform game processing based on acceleration.
2. Description of the Background Art
Conventionally, as disclosed in, e.g., Japanese Laid-Open Patent Publication No. 2007-241655 (hereinafter, referred to as Patent Document 1), there are game apparatuses that perform game processing using acceleration data outputted from an acceleration sensor included in an input device (see Patent Document 1). A movement determination apparatus disclosed in Patent Document 1 determines a moving direction of an input device, based on transition in acceleration data outputted from an acceleration sensor.
However, in the case of using the movement determination apparatus to determine a direction in which the input device has been swung, determination for various types of swings cannot be performed by single determination processing. For example, in the case of playing a tennis game in a virtual game world by swinging the input device, the above movement determination apparatus is not intended to realize a shot in accordance with an actual tennis swing although, in actual tennis play, various types of shots can be hit with different racket swing directions. Also, in the case of performing operations by swinging the input device, there is often a desire to perform different operations by changing a swing strength or the like even when performing the operations with a same swing direction. However, if such swing operations are determined only based on fixed swing directions, the above differences in the operations cannot be distinguished.